package com.gyh.system.sys.utils;

import java.security.MessageDigest;
import java.util.UUID;

import com.gyh.system.common.exception.RException;

/**
* @author 作者 gyh:
* @version 创建时间：2018年4月26日 下午4:56:44
* 
*/
public class TokenGenerator {
	 public static String generateValue() {
	        return generateValue(UUID.randomUUID().toString());
	    }

	    private static final char[] hexCode = "0123456789abcdef".toCharArray();

	    public static String toHexString(byte[] data) {
	        if(data == null) {
	            return null;
	        }
	        StringBuilder r = new StringBuilder(data.length*2);
	        for ( byte b : data) {
	            r.append(hexCode[(b >> 4) & 0xF]);
	            r.append(hexCode[(b & 0xF)]);
	        }
	        return r.toString();
	    }

	    public static String generateValue(String param) {
	        try {
	            MessageDigest algorithm = MessageDigest.getInstance("MD5");
	            algorithm.reset();
	            algorithm.update(param.getBytes());
	            byte[] messageDigest = algorithm.digest();
	            return toHexString(messageDigest);
	        } catch (Exception e) {
	            throw new RException("生成Token失败", e);
	        }
	    }
}
